The present invention relates to an electric machine with a winding support assembly and with a measuring system.
Nothing in the following discussion of the state of the art is to be construed as an admission of prior art.
At least the stator of electric machines includes a winding system that has to be connected in an end region of this electric machine. The lead-out wires of the winding system can be connected by manually welding or soldering. Insulating tubing is typically placed over the welded or soldered connections. The insulating connections are subsequently attached to a coil bobbin with cable ties.
German patent publication no. DE 15 88 986 discloses methods and systems for attaching windings, in particular end turns. An attachment device for the winding strands of an electric machine is described, wherein the winding strands are held together by an holder with fingers that hold the connecting wires.
German patent publication no. DE 23 52 946 describes a stator for induction machines, whereby each of the end turns of the exciter winding that projects from both sides of the laminated stator is provided with a tight-fitting shaped body that is pressed on. The shaped body is made of an insulating lattice structure, whereby the insulating lattice structure of the shaped body has pockets arranged around the periphery that receive the connecting ends of the winding strands. The winding strands are connected by soldering, welding or crimp sleeves. Disadvantageously, the location of the lead-out wires and/or the end turns is fixed, while the lead-out wires are neither properly routed nor reliably connected.
The aforementioned disadvantages in these electromagnetic assemblies, in particular electric motors, for example servo movers, can be eliminated by using a wiring support assembly. Such wiring support assemblies are structures that guide the lead-out wires through a meander-like configuration, thereby ensuring that the required air gaps and leakage paths are maintained and that the wires are properly attached. The wiring support assembly is preferably manufactured as an injection molded part and can be mass-produced at low-cost.
In addition, sensors that monitor various motor parameters are increasingly integrated in electromagnetic assemblies, in particular electric motors. Such motor parameters are, for example, the motor acceleration, the motor temperature, in particular the winding temperature, etc. Particularly the winding temperature is a critical parameter in electric motors that operate at their rated maximum power. The maximum allowable winding temperature determines the efficiency of the electric motor. The motor can fail or be destroyed if the allowable winding temperature is exceeded. Monitoring the winding temperature, in particular in high-efficiency drives, is therefore of extreme importance. Therefore, in particular temperature sensors are integrated in or on motors. Other sensors useful for measurement and monitoring purposes are acceleration sensors, vibration sensors or noise sensors, etc. The electromagnetic assemblies, in particular electric motors, for example servo motors, must be able to endure high vibration and shock loads without the risk of failure. It is therefore important to securely attach and/or to integrate the sensors in or on the motor and also to guarantee their functionality, in particular for temperature measurements. For example, if an air gap is created between the winding and the sensor, then the time constant of the protective circuits can change, so that the motor can be completely destroyed, for example as the result of a fire, before the protective circuit can respond to the increase in temperature. The sensors, in particular temperature sensors, so far have been mechanically attached to the winding, for example by cable ties. The produced air gap is filled by immersing the winding in a resin. Disadvantageously, however, the size of the gap is then not defined. This changes the time constant of the protective circuit, which depends on the size of the gap, making the motor protection unreliable.
It would therefore be desirable and advantageous to provide an improved electric machine with a sensor having improved monitoring performance.